1. Related Field
The present invention relates to the field of distributed power arrangements preventing circulating loop currents within said arrangements.
The present invention relates to a power supply arrangement for distribution of power from a Direct Current, DC, power source having a positive terminal and a negative terminal to at least a first and a second DC power consumer, comprising: a first DC power consumer connected to said negative terminal of said DC power source by means of at least a first return line, a first DC-DC switching power converter connected to said first DC power consumer by means of at least a first supply line, and connected to said positive terminal of said DC power source, a second DC power consumer connected to said negative terminal of said DC power source by means of at least a second return line, a second DC-DC switching power converter connected to said second DC power consumer by means of at least a second supply line, and connected to said positive terminal of said DC power source.
2. Description of Related Art
Today, there exist various examples of power arrangements comprising a plurality of converters and consumers, i.e. loads, connected to the same DC power source, which exhibit circulating DC currents in ground loop, i.e. return loop currents, created by connections between chassis or fuselage and said consumers. These circulating ground loop currents give raise to unintended voltage drops and emitted radiation causing electromagnetic interference, EMI. One solution for preventing circulating ground loop currents is to include a transformer in the power conversion providing galvanic isolation, but transformers are heavy and bulky, and may increase the level of common-mode currents. Another solution provides diodes in the return lines, but this solution leads to voltage drop and thus power losses, whereby normal functions of the equipment comprising said power arrangement may be interfered.
U.S. Pat. No. 5,990,757 shows a solution for preventing ground loop currents in power supply arrangements comprising switched converters connected in parallel to multiple loads consisting of diodes arranged in each power supply line. However this solution leads to power losses.
These present solutions are restricted to heavy and bulky transformers and leads to reduction in voltage in the power arrangement.
There is thus a need for an improved solution and power supply arrangement removing the above mentioned disadvantages.